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	<title>BOOST_PP_SUB</title>
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		The <b>BOOST_PP_SUB</b> macro expands to the difference between its arguments.
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	<h4>Usage</h4>
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			<b>BOOST_PP_SUB</b>(<i>x</i>, <i>y</i>)
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	<h4>Arguments</h4>
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			<dt>x</dt>
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				The minuend of the operation.&nbsp;
				Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.
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			<dt>y</dt>
			<dd>
				The subtrahend of the operation.&nbsp;
				Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.
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	<h4>Remarks</h4>
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			If the difference between <i>x</i> and <i>y</i> is less than <i>0</i>, the result is saturated to <i>0</i>.
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			Previously, this macro could not be used inside <b>BOOST_PP_WHILE</b>.&nbsp;
			There is no longer any such restriction.&nbsp;
			It is more efficient, however, to use <b>BOOST_PP_SUB_D</b> in such a situation.
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	<h4>See Also</h4>
		<ul>
			<li><a href="limit_mag.html">BOOST_PP_LIMIT_MAG</a></li>
			<li><a href="sub_d.html">BOOST_PP_SUB_D</a></li>
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	<h4>Requirements</h4>
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			<b>Header:</b> &nbsp;<a href="../headers/arithmetic/sub.html">&lt;boost/preprocessor/arithmetic/sub.hpp&gt;</a>
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	<h4>Sample Code</h4>
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#include &lt;<a href="../headers/arithmetic/sub.html">boost/preprocessor/arithmetic/sub.hpp</a>&gt;

<a href="sub.html">BOOST_PP_SUB</a>(4, 3) // expands to 1
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		<i>� Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
		</br><i>� Copyright Paul Mensonides 2002</i>
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		<p><small>Distributed under the Boost Software License, Version 1.0. (See
		accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
		copy at <a href=
		"http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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